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防空C^3I通信网分布式仿真

系统仿真学报 2001年第4期13卷 481-484页

作者：钟联炯罗钧钟升耿朝阳西安工业学院西安710032 西安通信学院西安710106

介绍防空C3I通信网仿真中信息格式、通信站点表示、LAN网仿真、子网仿真及用虚拟时间同步多机分步式仿真管理。本文提到的仿真建模技术对其它通信网仿真有参考价值。

关键词：分步式仿真虚拟时间仿真防空C^3I通信网计算机仿真

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IP网络中QoS保证方法研究

山西电子技术 2009年第5期 83-84页

作者：张荣宋宇解放军第61413部队西安通信学院

IP化是承载网发展的技术方向。QoS的本质是为用户提供有保障的网络资源来满足用户的需要。针对IP网络中常用的QoS保证方法进行了阐述,分析了其技术要点和特点,并指出了它们的局限性。

关键词： IP网承载网 QoS

High-Efficiency Wideband Transmitarray Antenna Using Polarization-Rotating Elements with Parasitic Stubs

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Chinese Journal of Electronics 2024年第2期33卷 496-503页

作者： xi WANG Yuandan DONG University of Electronic Science and Technology of china

A high-efficiency polarization-rotating transmitarray antenna(TA) using wideband elements is proposed for millimeter-wave applications. The polarization-rotating element consists of three metallic layers and two substrates. Orthogonal polarizers are employed on the top and bottom of the element. And the split ring with a parasitic stub on the middle layer is symmetric about the diagonal, performing the polarization rotation and phase compensation simultaneously. A parasitic stub is designed to decrease transmission loss and broaden the bandwidth. The periodicity of the element is only 1/4 wavelength at 30 GHz. A prototype TA with 28 × 28 elements is designed, fabricated, and measured. The measured peak gain reaches 27.5 d Bi at 37.8 GHz. The 1-d B gain drop bandwidth is 30.8–40 GHz(26.0%).The aperture efficiency reaches as high as 71% at 31.5 GHz. Within the bandwidth of 26.5–38.8 GHz(37.7%), the aperture efficiency is higher than 50%. The proposed polarization-rotating TA features wide bandwidth and high efficiency, demonstrating great application potential for 5G millimeter-wave communication.

关键词： Wavelength measurement Transmitting antennas Prototypes Apertures Gain measurement Propagation losses Broadband antennas

Variational Neural Inference Enhanced Text Semantic communication System

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china communications 2024年第7期21卷 50-64页

作者： Zhang xi Zhang Yiqian Li Congduan Ma xiao School of Electronics and communication Engineering Sun Yat-Sen UniversityShenzhen 518107China Guizhou University State Key Laboratory of Public Big Data Guiyang 550025China Shenzhen Key Laboratory of Navigation and communication Integration Shenzhen 518107China School of Computer Science and Engineering Sun Yat-Sen UniversityGuangzhou 510006China

Recently,deep learning-based semantic communication has garnered widespread attention,with numerous systems designed for transmitting diverse data sources,including text,image,and speech,*** efforts have been directed toward improving system performance,many studies have concentrated on enhancing the structure of the encoder and ***,this often overlooks the resulting increase in model complexity,imposing additional storage and computational burdens on smart ***,existing work tends to prioritize explicit semantics,neglecting the potential of implicit *** paper aims to easily and effectively enhance the receiver's decoding capability without modifying the encoder and decoder *** propose a novel semantic communication system with variational neural inference for text ***,we introduce a simple but effective variational neural inferer at the receiver to infer the latent semantic information within the received *** information is then utilized to assist in the decoding *** simulation results show a significant enhancement in system performance and improved robustness.

关键词： deep learning semantic communication variational neural inference

Pupillometry Analysis of Rapid Serial Visual Presentation at Five Presentation Rates

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Tsinghua Science and Technology 2024年第2期29卷 543-552页

作者： xi Luo Yanfei Lin Rongxiao Guo xirui Zhao Shangen Zhang xiaorong Gao School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China School of Computer and communication Engineering University of Science and Technology BeijingBeijing 100083China School of Medicine Tsinghua UniversityBeijing 100084China

In this study,the effect of presentation rates on pupil dilation is investigated for target recognition in the Rapid Serial Visual Presentation(RSVP)*** this experiment,the RSVP paradigm with five different presentation rates,including 50,80,100,150,and 200 ms,is *** pupillometry data of 15 subjects are collected and *** pupillometry results reveal that the peak and average amplitudes for pupil size and velocity at the 80-ms presentation rate are considerably higher than those at other presentation *** average amplitude of pupil acceleration at the 80-ms presentation rate is significantly higher than those at the other presentation *** latencies under 50-and 80-ms presentation rates are considerably lower than those of 100-,150-,and 200-ms presentation ***,no considerable differences are observed in the peak,average amplitude,and latency of pupil size,pupil velocity,and acceleration under 100-,150-,and 200-ms presentation *** results reveal that with the increase in the presentation rate,pupil dilation first increases,then decreases,and later reaches *** 80-ms presentation rate results in the largest point of pupil *** correlation is observed between pupil dilation and recognition accuracy under the five presentation rates.

关键词： pupil dilation presentation rate Rapid Serial Visual Presentation(RSVP)

Gamma Approximation Based Multi-Antenna Covert communication Detection

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china communications 2024年第9期21卷 90-97页

作者： Wan Pengwu Chen Dongrui Wang Danyang Hui xi Peng Kang School of communications and Information Engineering&School of Artificial Intelligence Xi’an University of Posts and TelecommunicationsXi’an 710121China Key Laboratory of Integrated Service Networks School of Telecommunications EngineeringXidian UniversityXi’an 710071China

Covert communication technology makes wireless communication more secure,but it also provides more opportunities for illegal users to transmit harmful *** order to detect the illegal covert communication of the lawbreakers in real time for subsequent processing,this paper proposes a Gamma approximation-based detection method for multi-antenna covert communication ***,the Gamma approximation property is used to calculate the miss detection rate and false alarm rate of the monitor *** the optimization problem to minimize the sum of the missed detection rate and the false alarm rate is *** optimal detection threshold and the minimum error detection probability are solved according to the properties of the Lambert W ***,simulation results are given to demonstrate the effectiveness of the proposed method.

关键词： covert communication detection Gamma approximation Lambert W function multi-antenna technique

Event-triggered-based distributed differential game guidance laws

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Kongzhi yu Juece/Control and Decision 2024年第11期39卷 3745-3754页

作者： xi, A-xing Cai, Yuan-Li Control Engineering Research institute Xi’an Jiaotong University Xi’an 710049 China

To reduce computational loads and save communication resources of cooperative multi-missile systems based on the event-triggered mechanism, the distributed differential game guidance laws are investigated. First, the cooperative multi-missile interception problem is converted into multi-player zero-sum differential games. The proposed guidance laws are derived by addressing the couple event-triggered-based Hamilton-Jacobi-Bellman equation, which is solved by using the adaptive dynamic programming technique. Meanwhile, adaptive weight tuning laws and event-triggered conditions are designed. The proposed guidance laws can guarantee the stability of the nonlinear multi-missile system, which is proved using the Lyapunov method. Then, the estimated weights of the neural network and consensus tracking errors are ensured to be uniformly ultimately bounded. Besides, a minimal inter-sample time is established for avoiding the Zeno behavior. Finally, some experiments are provided to illustrate the effectiveness of the proposed guidance laws. Compared with traditional distributed differential game guidance laws, the proposed guidance law reduces the number of state updates of the cooperative system controller by 65.36 %. The computational burden and communication resources of the control system can be greatly reduced. © 2024 Northeast University. All rights reserved.

关键词： Lyapunov methods

Neuro- and immuno-modulation mediated by the cardiac sympathetic nerve: a novel insight into the anti-ischemic efficacy of acupuncture

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Journal of Traditional Chinese Medicine 2024年第5期44卷 1058-1066页

作者： xi Hanqing LI xia ZHANG Ziyi CUI xiang JING xianghong ZHU Bing GAO xinyan institute of Acupuncture and Moxibustion China Academy of Chinese Medical Sciences

communication between sympathetic nerves and the immune system is a crucial and active process during myocardial ischemia(MI), as myocardial damage and inflammatory stimuli concurrently occur. Sympathetic nerves undergo structural and functional changes after MI,leading to adverse left ventricular(LV) remodeling and heart failure(HF). The complex inflammatory response to MI, including local myocardial anti-inflammatory repair and systemic immune reactions, plays a key role in adverse LV remodeling. Here, we review the progressive structural and electrophysiological remodeling of the LV and the involvement of sympathetic tone in complex and dynamic processes that are susceptible to MI pathological conditions. Acupuncture has been reported to effectively improve cardiac function, eliminate arrhythmia, and mitigate adverse LV remodeling via somatosensory regulation after MI. Moreover,acupuncture has an anti-inflammatory effect on the pathological process of myocardial ischemia. In this Review, we aim to summarize the involvement of sympathetic nerve activation in the neuro-immune modulation of structural and functional cardiac changes after MI. As a noninvasive method for sympathetic regulation, acupuncture is an ideal option because of its anti-ischemic efficacy. A better understanding of the neural circuitry that regulates cardiac function and immune responses following MI could reveal novel targets for acupuncture treatment.

关键词： acupuncture myocardial ischemia neuroinflammatory diseases review sympathetic nerves

Generation of macroscopic entanglement in ensemble systems based on silicon vacancy centers

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Chinese Physics B 2024年第9期33卷 308-315页

作者： Jian-Zhuang Wu Ying xi Bo-Ya Li Lian-E Lu Yong-Hong Ma School of Science Inner Mongolia University of Science and TechnologyBaotou 014010China

Entanglement in macroscopic systems,as a fundamental quantum resource,has been utilized to propel the advancement of quantum technology and probe the boundary between the quantum and classical *** study focuses on a unique hybrid quantum system comprising of an ensemble of silicon vacancy(SiV)centers coupled to phononic waveguides in diamond via strain *** employing two sets of time-dependent,non-overlapping driving fields,we investigate the generation process and dynamic properties of macroscopic quantum entanglement,providing fresh insights into the behavior of such hybrid quantum ***,it paves the way for new possibilities in utilizing quantum entanglement as an information carrier in quantum information processing and quantum communication.

关键词： quantum entanglement silicon vacancy centers diamond waveguide